Shock absorbing mechanism for pin carriages



United States Patent 0, Sweden, assignors to Aktiebolaget Addo, Malmo,Sweden, a corporation of Sweden Filed Mar. '16, 1956, Ser. No. 571,906Claims priority, application Sweden Mar. 24, 1955 6 Claims. (Cl. 235-60)This invention relates to calculating machines having a setting pincarriage.

In the last few years, attempts have been made to increase the speed ofcalculating machines more and more. In the course of experiments aimedat increasing machine speed a plurality of new problems such asrebounding calculating means and machine noise have been encountered.

The object of the invention is to provide a solution of one such problemin calculating machines having a machine frame, a setting pin carriage,setting pins on said carriage, supporting means supporting said carriageon said machine frame for reciprocation in a first direction, andtransmitting means on said machine frame movable in a sensing courseinto bearing engagement with said setting pins in a second directionsubstantially at right angles to said first direction. In such acalculating machine the invention provides resilient means forming partof said supporting means and allowing said carriage to move yieldinglyin relation to said machine frame out of a position of restapproximately in said second direction.

Further objects and features of as well as the advantages gained by theinvention will appear from the following description, reference beinghad to the accompanying drawing diagrammatically illustrating twoembodiments of the invention.

-Fig. 1 is a plan view, partly in section, of the mechanism according tothe invention;

Fig. 2 is a view of the mechanism in Fig. l as seen from the right, oneframe end wall being partly broken away;

Fig. 3 is a view similar to Fig. 1 of another embodiment of theinventio'n.

With reference to Fig. 1, two side walls 1 and 2 and a front wall 3 areshown of the frame of a calculating machine. Extending between the sidewalls 1, 2 and in parallel with the front wall 3, is a rod 4 on which asetting pin carriage 5 of prior art construction is movably mounted bymeans of lugs 6. In the usual manner, the carriage 5 has a plurality ofsetting pins 7 arranged in mutually perpendicular rows. Some of saidsetting pins 7 only are shown in the drawing for the sake of clarity. Inthe normal position of the machine in which the keyboard of the machineis zero set, the carriage 5 occupies a starting position adjacent a stop8 connected with the rod 4. When numbers are entered on the machinekeybo'ard (not shown), the setting pin carriage 5 is displaced throughone step to the left as seen in Fig. 1 along the rod 4 for each digitentered, and during this stepwise movement row after row of setting pinswill be placed in the path of movement of a plurality of transmittingmeans 9, only one of which is shown in the drawing for the sake ofclarity. For each digit key depressed a setting pin 7 in one of thecarriage setting pin rows perpendicular to the rod 4 is raised in theusual manner which is not therefore shown in detail. The transmittingmeans 9 shown in the drawing is in the form of a rod mounted in a knownmanner on the machine frame so as to be movable approximately inparallel with the upper side of the carriage 5 and at right angles tothe rod 4 in the direction indicated by the arrow 10 in Fig. 2. Said rod9 has a downwardly directed projection 11 which during the sensingcourse of the rod effected in the direction of the arrow 10 meets thesetting pin 7 raised by the digit key, thus being stopped by saidsetting pin whereby calculating means (not shown) of a known type areset fo'r the value corresponding to that of the digit key depressed.After the digits entered on the carriage 5 have been transmitted by thetransmitting means 9 in this way, the carriage 5 is returned by elementsnot shown to its starting position in which it is in bearing engagementwith the stop 8.

The rod 4 is mounted in the following manner to permit rapid operationof the machine without the risk that the transmitting means 9 willrebound to a detrimental ex tent against the setting pins 7 and that thecarriage 5 will rebound against the stop 8 at its return movement sothat calculating errors and noise arise. The ends of the rod 4 extendthrough slots 12 in the frame end walls 1, 2. Said slots 12 are elongatein a direction parallel to that of direction 10, and they guide the rodin such a way that it is movable on one hand in its longitudinaldirection and on the other at right angles toits longitudinal axisapproximately in the direction 10 of the sensing course of thetransmitting means 9, while at the same time, as

indicated in Fig. 2, they limit the vertical movement of rod 4, andprevent it from moving substantially in a vertical direction, i.e. in adirection perpendicular both to the axis of ro'd 4 and to the direction10 of the sensing course of transmitting means 9. In unactuatedcondition the rod 4 is held in a normal position by resiliently yieldingmeans. On each end of the rod 4 outside the respective frame end walls1, 2 there are rotatively mounted two adjacent arms 13, 14 and 15, 16,respectively. The said arms are plate-shaped. In each arm pair one armhas a projection 17 at the upper end while the other arm has aprojectio'n 18 at the lower free end, and these two projections areinterconnected by means of a pull spring 19 interposed between them.Besides, each of the arms has a hole 20 by means of which they arepassed onto the respective end of a rod 21 secured in the frame endwalls 1, 2. The hole 20 in each arm 13 to 16 is substantially square,except for one corner of the square which is cut away by an edge 22making an angle of approximately 45 with the adjacent square sides andmerging with the adjacent square sides approximately at the middle ofthe length that these sides would have if they were the sides of a realsquare. The opposite and mutually parallel sides of the hole 20 arespaced a somewhat greater distance apart than the diameter of the rod21. The edge of each hole 20 which is remote from the rod 4 isapproximately at right angles to the connecting line between the axes ofthe rods 4 and 21, and the oblique edge 22 of each hole faces away fromthe rod 4 and is situated on the same side of said connecting line asthe projection 17 and 18, respectively, of the respective arms 13 to 16.The spring 19 urges the oblique edges 22 into engagement with the rod 21whereby a component thrust arises which is directed away from the rod 4along the connecting line between the axes of the rods 4 and 21 andwhich thus results in a displacement of the rod 4 together with arms 13to 16 to the left as seen in Fig. 2, the side edges of the holes 20remote from the rod 4 being pressed against the rod 21 which isstationary in relation to the frame end walls 1, 2. In the position ofrest of the machine, the rod 4 is therefore held at a determineddistance from the rod 21 in a normal position. When the projections 11of the transmitting means 9 meet setting pins 7 on the carriage 5 duringtheir sensing courses, there arises a shook which is taken upresiliently and softly without any appreciable rebound of thetransmitting means 9 against the setting pins 7 by the rod 4 and thearms 1316 moving rearwardly while the oblique edges 22 of the openings20 slide against the stationary rod 21 and move the arm projections 17,18 apart against the action of the spring 19 which immediately after theshock returns the projections 17, 18 to their original spaced apartposition, while the oblique hole edges 22 slide back against the rod 21so that the ro'd 4 and thereby the carriage 5 are returned to apredetermined position of rest which is delined by the lateral holeedges remote from the rod 4 bearing against the rod 21 under the actionof the springs 19. The movement of the rod 4 towards the rod 21 underthe action of the shocks of the transmitting means 9 are restricted to acertain maximum in that the vertical edges of holes 20 closest to therod 4 will bear against the rod 21 during the movement of the rod 4 andthus of the arms 1316 towards said rod 21, whereby said edges constitutestops for limiting the movement of the rod 4 out of the position of resttowards the rod 21.

Experiments have shown that to obtain the best possible damping of theshocks of the transmitting means 9 against the setting pins 7 withoutany appreciable rebound and noise, the left-hand spring 19, as seen inFig. 1, should be stronger than the right-hand one. The reason for thisconstruction is that the shock energy to be absorbed varies from onecomputation to another in accordance with the number of setting pinsraised (the number of shocks by transmitting means 9 abutting againstraised setting pins during the sensing course), the number ofsimultaneous impacts between raised setting pins and transmitting meansand to a certain extent also the dis tance that the transmitting meanshave to move to abut the raised setting pins. A low shock energy is bestdamped by a weak spring action and a high shock energy demands a strongspring action. When the shock energy is low the shock is dampedsubstantially only by yielding of the weak right-hand spring 19 in Fig.1 so that in a broad sense the rod 4 is fulcrumed about its left-handend support formed by the arms 13, 14 gripping the rod by means of thestrong left-hand spring 19, which will not yield or yield only to asmall extent. When the shock energy is high the shock is damped partlyby complete yielding of the weak right-hand spring 19 in Fig. 1 untilthe left-hand vertical edges of the openings '20 in the arms 15, 16 inFig. 2 abut against the rod 21 and partly by yielding of the strongleft-hand spring 19 in Fig. 1.

The arms 15, 16 are disposed on the righthand end of the rod 4, as seenin Fig. 1, between a locking plate 23 and a rubber disk 24. The lockingplate 23 is inserted in a groove at the end of the rod 4. The stop 8 isin the form of a sleeve and loosely passed onto the rod 4. It

has a flange 25 which is in bearing engagement with the face of therubber disk 24 facing away from the arms 15,

16. A further rubber disk 26 is interposed between the flange 25 and theframe end wall 2. The arms 13, 14 at the left-hand end of the rod 4, asseen in Fig. l, are mounted on said rod between a locking plate 27,inserted in a groove at'the rod end, and a cup-shaped rubber buffer 28which is applied with its cup edge against the frame end wall 1 andwhich, in the position of rest of the machine, holds the assembly formedby parts 8, 15, 16, 23-26 snugly moved together with the rubber disk 26bearing against the frame end wall 2 so that the rod 4 and the stop 8are held in a definite position of rest longitudinally of the rod 4.When the carriage 5 is returned to its starting position by means of theprior art elements (not shown) after the transmitting means 9 haveperformed their sensing course, the carriage 5 meets the stop 8, theresulting shock being resiliently taken up without any appreciablerebound and noise in that the stop 8 resiliently yields to the carriage5 arriving in starting position, because said stop canmove to the rightas the longitudinal direction of the rod 4.

4 seen in Fig. 1 while carrying the rod 4 along and compressing therubber buffer 28.

Another way of realizing the inventive idea is shown in Fig. 3. The rod4 is here immovably secured in the end walls of the machine frame, ofwhich the end wall 2 only is shown in Fig. 3. The lugs 6 of the carriage5 have holes 29 through which the rod '4 extends and which in thedirection 10 of the sensing course of the transmitting means 9 has alarger extension that the rod 4 Whereby the carriage is movable inrelation to the rod approximately in the direction 10 of the sensingcourse of the transmitting means 9 as well as in the opposite direction.Bores 30 are provided in the lugs 6. Said bores are at rightangles tothe rod 4 and open into the holes 29. Balls 31 are inserted in saidbores 30 and are held pressed against the rod 4 by springs 32 in saidbores 30 so that the carriage 5 in a position of rest is heldresiliently displaced by the springs 32 as far'as possible in adirection opposed to the direction 10, the portion of the wall of theholes 29, which is opposed to the bores 30, hearing against the rod 4.When the transmitting means 9 perform their sensing course in thedirection 10 and meet the adjusted setting pins 7 of the carriage 5, theshock is resiliently and softly taken up by the carriage being displacedapproximately in the direction 10 in respect of the stationary rod 4,while the balls 31 are pushed into the bores 30 and the springs32 arecompressed, which springs after the shock return the carriage to theposition of rest shown in Fig. 3.

Pistons may be substituted for the balls 31. It is also possible tosubstitute a leaf spring or the like for each spring mechanism 3t)32,which leaf spring is secured to the carriage and resiliently bearsagainst the rod. The means, e.g., lugs 6, by which the carriage 5 ismounted on the rod 4, can also be mounted in their entirety on thecarriage in such a way as to be resiliently movable with respect to thecarriage approximately in the direction 10 and in the oppositedirection. The spring mechanism 3032 arranged in connection with onemounting means 6 may have a steeper spring characteristic than the othermechanism, in analogy with what "has been described for the springmechanisms of the rod 4 in the embodiment according to Figs. 1 and 2.

Inthe embodiment according to Fig. 3, the frame end wall 2 properconstitutes the stop for arresting the carriage 5 during its returnmovement to the right as seen in Fig. 3. The right-hand lateral edge ofthe carriage 5 has a bore 33 accommodating a spring 34 which tends topush a piston 35 out of the bore into a position of rest in which itbears against a stop (not shown) in the bore and in which the right-handend of the piston projects from the carriage side face so that duringits return movement the carriage will hit the end wall 2 with the piston35. As a result, said piston is pushed into the bore 33, compressing thespring 34 and resiliently damping the shock against the end wall 2.After the shock action has ceased, the spring 34 returns the piston 35to its position of rest so that the carriage 5 will occupy apredetermined starting position in respect of It is obvious that insteadof the spring-actuated piston 35 it is possible to arrange some otherkind of a spring buffer on the carriage 5 for damping the shock of thecarriage against the end wall 2 during the return movement of thecarriage.

While the invention has been described in the foregoing in twoembodiments thereof, it must not be regarded as restricted thereto, formany modifications may be resorted to within the scope of the invention,such as is defined in the appendant claims, as will readily be realizedby those skilled in the art. It should be observed especially that it ispossible to use in one and the same machine both the embodimentaccording to Figs. "1 and 2 and the one according toFig. 3.

What we claim and desire to secure by Letters Patent is:

1. In a calculating machine a machine frame, a setting pin carriage,setting pins on said carriage, supporting means supporting said carriageon said machine frame for reciprocation in a first direction,transmitting means on said machine frame movable in a sensing courseinto bearing engagement with said setting pins in a second directionsubstantially at right angles to said first direction, guide meansallowing substantial movement of said carriage in said second directionand preventing substantial movement thereof in a direction perpendicularto said first and second directions, and resilient means acting on saidcarriage in a direction opposite and parallel to said second directionand urging it to a position of rest.

2. In a calculating machine frame, a rod mounted in said frame, asetting pin carriage mounted on said rod for reciprocation therealongparallel to a first axis which is the longitudinal axis of said rod,parallel setting pins mounted in said carriage for reciprocationparallel to a second axis, said second axis being parallel to thelongitudinal axes of said setting pins and perpendicular to said firstaxis, transmitting means mounted on said frame for reciprocationparallel to a third axis which is perpendicular to said first and secondaxes, said transmitting means being movable in a sensing directionparallel to said third axis and into bearing engagement with saidsetting pins, rod guide means in said frame allowing substantialmovement of said rod in a direction parallel to said third axis andpreventing substantial movement of said rod in a direction parallel tosaid second axis, and resilient means acting on said rod in a directionparallel to said third axis, urging said rod to a position of rest.

3. In a calculating machine a machine frame, a rod, first and second rodmounting means at the respective opposite ends of said rod mounting saidrod in said frame, a setting pin carriage mounted on said rod forreciprocation therealong parallel to a first axis which is thelongitudinal axis of said rod, parallel setting pins mounted in saidcarriage for reciprocation parallel to a second axis, said second axisbeing parallel to the longitudinal axes of said setting pins andperpendicular to said first axis, transmitting means mounted on saidframe for reciprocation parallel to a third axis which is perpendicularto said first and second axes, said transmitting means being movable ina sensing direction parallel to said third axis and into bearingengagement with said setting pins. first and second rod guide means insaid frame adjacent respectively to said first and second rod mountingmeans, each said rod guide means allowing substantial movement of saidrod in a direction parallel to said third axis and preventingsubstantial movement of said rod in a direction parallel to said secondaxis, and first and second resilient means, each comprising respectivelya portion of said first and second rod mounting means, each saidresilient means acting on said rod in a direction parallel to said thirdaxis and urging said rod into a position of rest.

4. A calculating machine as defined by claim 3, said first and secondresilient means being of substantially diflerent strengths, whereby eachacts on said rod with a substantially different force.

5. A calculating machine as defined by claim 3, one end of said rodcomprising a first member, a second member rigidly fixed to said frame,said second member being spaced from said first axis, one of saidresilient means comprising a pair of plate members pivotally attached toone of said first and second members, a cam surface on each of saidplate member, each cam surface facing the other one of said first andsecond members and being on the opposite side of a line joining thecenters of said first and second members, and spring means urging saidplate members to swing toward each other about said one of said firstand second members to press said cam surfaces against said other one ofsaid first and second members and thereby urge said rod toward aposition of rest.

6. In a calculating machine as defined by claim 5, said one of saidfirst and second members being said one end of said rod.

References Cited in the file of this patent UNITED STATES PATENTS2,229,980 Landsiedel Jan. 28, 1941 2,490,200 Boyden Dec. 6, 19492,823,854 Walther Feb. 18, 1958 FOREIGN PATENTS 866,868 France June 9,1941 731,096 Germany Feb. 2, 1943 851,267 Germany Oct. 2, 1952

